.modal-mask{
    position: absolute;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.4);
    z-index: 99;
}
.modal-body{
    background: white;
    border-radius: 5px;
    max-height: 500px;
    width: 90%;
    margin: 100px auto;
  
    position: absolute;
    left:50%;
    top:40%;
    transform: translate(-50%, -50%);
}
.title{
    text-align: center;
    height: 80px;
    line-height: 80px;
    border-bottom: 1px solid #eee;
}